Toner cartridge, toner supplying mechanism and shutter

The present invention relates to a toner cartridge, a toner supplying mechanism and a shutter for an electrophotographic image formation.

In the field of an electrophotographic type image forming apparatus, it is known that elements such as a photosensitive drum and/or a developing roller as a rotatable member contributable to image formation are unified into a cartridge, which is detachably mountable to the main assembly of the image forming apparatus (main assembly).

As one of such a cartridge detachably mountable to the image forming apparatus, there is known a toner cartridge which is exchangeable and which does not include the photosensitive drum or the developing roller, the toner cartridge containing toner (developer) which is to be consumed with the image formation.

With such a structure, the toner (developer) is discharged through the discharge opening from the toner cartridges into a developing device including the developing roller and so on. In addition, in order to prevent the toner from leaking out through the discharge opening, an open/close member such as a shutter for opening and closing the discharge opening is provided.

Japanese Laid-open Patent Application Hei 7-199623, for example discloses a structure in which when a cylindrical toner cartridge (developer supply container) is mounted to the main assembly of the image forming apparatus, the toner cartridge is rotated by which the shutter is opened.

It is an object of the present invention to provide a further development of the above-described conventional structure.

According to a first aspect of the present invention, there is provided a toner cartridge detachably mountable to a receiving device, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner from said accommodating portion into the receiving device; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being rotatable relative to said container between (a) an opening position for causing said closing portion to open said discharge opening and (b) a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion between (c) a engaging position for engagement with the receiving device to receive a force for moving said open/close member from the opening position to the closing position when said toner cartridge is dismounted from the receiving device and (d) a retracted position retracted from the engaging position, and wherein said engaging portion is movable from the retracted position to the engaging position with rotation of said open/close member from the closing position to the opening position.

According to a second aspect of the present invention, there is provided a toner cartridge detachably mountable to a receiving device, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner from said accommodating portion into the receiving device; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being rotatable relative to said container between (a) an opening position for causing said closing portion to open said discharge opening and (b) a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion between (c) a engaging position for engagement with the receiving device to receive a force for moving said open/close member from the opening position to the closing position when said toner cartridge is dismounted from the receiving device and (d) a retracted position retracted from the engaging position, and wherein said engaging portion is movable from the engaging position to the retracted position with rotation of said open/close member from the opening position to the closing position.

According to a third aspect of the present invention, there is provided a toner cartridge detachably mountable to a receiving device by a mounting operation including a rotating operation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner from said accommodating portion into the receiving device; and an open/close member including a closing portion for closing said discharge opening and a engaging portion movable relative to said closing portion, said open/close member being movable relative to said container between (a) a opening position for causing said closing portion to open said discharge opening and (b) a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion between (c) a engaging position for engagement with the receiving device to receive a force for moving said open/close member from the opening position to the closing position when said toner cartridge is dismounted from the receiving device and (d) a retracted position retracted from the engaging position, and wherein said engaging portion is movable from the retracted position to the engaging position with the rotating operation.

According to a fourth aspect of the present invention, there is provided a toner cartridge dismountable from a receiving device by a dismounting operation including a rotating operation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner from said accommodating portion into the receiving device; and an open/close member including a closing portion for closing said discharge opening and a engaging portion movable relative to said closing portion, said open/close member being movable relative to said container between (a) a opening position for causing said closing portion to open said discharge opening and (b) a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion between (c) a engaging position for engagement with the receiving device to receive a force for moving said open/close member from the opening position to the closing position when said toner cartridge is dismounted from the receiving device and (d) a retracted position retracted from the engaging position, and wherein said engaging portion is movable from the engaging position to the retracted position with the rotating operation.

According to a fifth aspect of the present invention, there is provided a toner cartridge detachably mountable to a receiving device, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner from said accommodating portion into the receiving device; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being movable relative to said container between (a) an opening position for causing said closing portion to open said discharge opening and (b) a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion between (c) a engaging position for engagement with the receiving device to receive a force for moving said open/close member from the opening position to the closing position when said toner cartridge is dismounted from the receiving device and (d) a retracted position retracted from the engaging position, and a retracted position moving portion for moving said engaging portion from the engaging position to the retracted position with movement of said open/close member from the opening position to the closing position.

According to a sixth aspect of the present invention, there is provided a toner cartridge for electrophotographic image formation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being rotatable relative to said container between an opening position for causing said closing portion to open said discharge opening and a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion is movable relative to said closing portion at least in a direction of a rotational axis of said open/close member, with rotation of said open/close member between the closing position and the opening position.

According to a seventh aspect of the present invention, there is provided a toner cartridge for electrophotographic image formation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being rotatable relative to said container between an opening position for causing said closing portion to open said discharge opening and a closing position for causing said closing portion to close said discharge opening, when said engaging portion is exposed at least toward an outside with respect to a direction of a rotational radius of said open/close member, and wherein said engaging portion is movable relative to said closing portion at least in the direction of the rotational radius of said open/close member, with rotation of said open/close member between the closing position and the opening position.

According to an eighth aspect of the present invention, there is provided a toner cartridge for electrophotographic image formation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner; and an open/close member including a closing portion for closing said discharge opening and an engaging portion movable relative to said closing portion, said open/close member being rotatable relative to said container between an opening position for causing said closing portion to open said discharge opening and a closing position for causing said closing portion to close said discharge opening, wherein said engaging portion including a first projection projecting toward an outside with respect to a direction of a rotational radius of said open/close member, and a second projection provided on said first projection and projecting toward a downstream side with respect to a direction in which said open/close member rotates relative to said container from the from the closing position to the opening position, and wherein said engaging portion is movable relative to said closing portion with rotation of said open/close member between the closing position and the opening position.

According to a ninth aspect of the present invention, there is provided a toner cartridge for electrophotographic image formation, said toner cartridge comprising a container including a accommodating portion for accommodating the toner and a discharge opening for discharging the toner; an open/close member movable relative to said container between an opening position for causing said closing portion to open said discharge opening and a closing position for causing said closing portion to close said discharge opening; a moving portion, provided on said container, for moving said engaging portion with movement of said open/close member from the opening position to the closing position.

According to a tenth aspect of the present invention, there is provided a shutter for use with a toner cartridge, said shutter comprising a main body portion having a substantially accurate configuration; a first arm portion provided at a longitudinal end portion of said main body portion and extending toward a widthwise end portion of said main body portion; and a first projection provided at a free end side of said first arm portion and projecting in a radially outward direction with respect to the arcuate configuration, wherein first projection is movable at least in a longitudinal direction of said main body portion.

The above-described conventional structure can be further developed.

Referring to the accompanying drawings, an electrophotographic image forming apparatus, a toner image forming portion and a toner cartridge will be described. The image forming apparatus is an apparatus capable of forming an image on the recording material through an electrophotographic image forming process, for example. For example, it may be an electrophotographic copying machine, an electrophotographic printer (LED printer, laser beam printer or the like) or an electrophotographic printer type facsimile machine.

In this embodiment, it is a monochromatic image forming apparatus including one toner image forming portion. However, the number of the toner image forming portions provided in the image forming apparatus is not limited to this example. For example, the image forming apparatus may include a plurality of toner image forming portions to form color images.

Similarly, as for the structures disclosed in the embodiments, the material, the arrangement, dimension or other values or the like are not limited to the disclosed examples, unless otherwise stated particularly. In the following description, “up” is based on the direction of the gravity when the image forming apparatus is installed.

The structures contributable to the improvement in the usability will be described in detail. More particularly, it is a related with crispness when a user mounts the toner cartridge to a developing unit (developing cartridge).

The general arrangement of the image forming apparatus will be described the first, and then the developing unit and the toner cartridge will be described in detail. An operation of mounting the toner cartridge to the developing unit is called “mounting operation”, and an operation of dismounting the toner cartridge from the developing unit is called “dismounting operation”.

§ 1. Electrophotographic Image Forming Apparatus:

is a side section of the image forming apparatus A according to this embodiment of the present invention. The image forming apparatus A shown inreceives image information from an external equipment such as a personal computer communicatably connected therewith. In accordance with image information received from the external equipment, the image forming apparatus A forms an image (toner image) with a developer (toner) on a recording material P (recording paper, OHP sheet, textile or the like) through an electrophotographic image forming process.

In the image forming apparatus A, the toner image forming portion (toner image forming unit) B is detachably mountable to a main assembly. The toner image forming portion (toner image forming unit) B of this embodiment comprises a drum unit (drum cartridge) C, the developing unit (developing device, developing cartridge) D and a toner cartridge E. The toner cartridge E is detachably mountable to the developing unit D. More particularly, the developing unit D is provided with a mounting portion for mounting the toner cartridge E, and constitutes a receiving device for receiving the toner cartridge E.

The toner image forming portion (toner image forming unit) can be deemed as a unit including a photosensitive drum and an element or elements actable on the photosensitive drum.

In this embodiment, the drum unit C, the developing unit D and the toner cartridge E are cartridges independently detachably mountable to the main assembly of the apparatus. In such a case, the drum unit C may be called a drum cartridge, and the developing unit D may be called a developing cartridge.

It is not inevitable that the drum unit C, the developing unit D and the toner cartridge E are in the form of such cartridges, respectively. For example, it is possible that the photosensitive drum (or drum unit including the photosensitive drum) is fixed in the main assembly, whereas the developing unit (developing cartridge) D and the toner cartridge E only are detachably mountable.

In addition, it is possible that the drum unit C and the developing unit D a unified into a single cartridge which is detachably mountable to the main assembly. The cartridge comprising the unified drum unit C and developing unit D may be called a process cartridge. In such a case, the toner cartridge E is mountable to and dismountable from the process cartridge. In such a case, the process cartridge is the receiving device. The image forming apparatus employing the process cartridge structure will be described in conjunction with Embodiment 4.

Furthermore, it is possible that the photosensitive drum and the developing unit are fixed in the main assembly, and the toner cartridge E only is detachably mountable to the main assembly. In such a case, the main assembly of the image forming apparatus per se is the receiving device for the toner cartridge E.

The structure including the receiving device (developing unit D) and the toner cartridge E in combination may be called a toner supply mechanism (toner supply unit, toner supplying device). In the toner supply mechanism, the toner is supplied from the toner cartridge E into the receiving device.

In this embodiment, the photosensitive drum as an image bearing member comprises a cylinder having a photosensitive layer and a flange or the like as a unit.

The mounting and dismounting of the cartridges are carried out by the user (operator). The main assembly (main assembly of the image forming apparatus) is the part of the image forming apparatus A except for the cartridges (drum unit C, developing unit D and toner cartridge E).

The drum unit C comprises the photosensitive drum (image bearing member), a charging roller, the cleaning bladeand so on as a unit, and in this embodiment, it is a cartridge (drum cartridge) detachably mountable to the main assembly. The developing unit D comprises a developing roller (developer carrying member)and so on as a unit, and in this embodiment, it is a cartridge (developing cartridge) detachably mountable to the main assembly. The toner cartridge E as the developer container comprises the toner container (developer accommodating container, container)for accommodating the toner t as the developer and so on, which are unified into a cartridge.

The photosensitive drumis rotatable in a direction indicated by an arrow a in. The surface of the rotating photosensitive drumis uniformly charged by the charging rolleras charging means. The photosensitive drumis exposed to a laser beam L supplied by way of the laser scanner (exposure means)in accordance with the image information, so that an electrostatic latent image is formed on the photosensitive drumin accordance with the image information. The toner t carried on the developing rollerdevelops the electrostatic latent image. By this, a toner image is formed on the photosensitive drum.

Referring to, a developing process in the toner image forming portion B will be described. A frameof the developing unit D as the receiving device rotatably supports the developing roller. The developing rollerreceive a driving force from a power source such as a motor (unshown) provided in the main assembly to rotate codirectionally with the peripheral surface of the photosensitive drum(arrow b in the Figure).

The toner t in a developing chamberis carried on the peripheral surface of the developing rollerwith a regulated layer thickness by a developing blade. When the layer thickness is regulated, the toner is triboelectrically charged. The charged toner develops the electrostatic latent image on the photosensitive drum.

In the developing unit D, the developing chamberis in fluid communication with a first toner accommodating portion (developer accommodating portion)through a first opening. A first toner feeding meansrotated by a driving source (unshown) feeds the toner t from the first toner accommodating portioninto the developing chamber.

In addition, a communicating portionis provided by a second opening (accommodation member opening, receiving port, receiving opening)and a third opening (container opening, discharge port, discharge opening). Through the communicating portion, the first toner accommodating portion (accommodation member accommodation chamber)is in fluid communication with the second toner accommodating portion (container accommodation chamber)of the toner cartridge E.

The second toner accommodating portionis the space in the containerfor accommodating the toner. The second toner accommodating portionis an accommodating portion (toner accommodating portion, developer accommodating portion) provided by the frame (container frame) of the container.

A third openingis formed in the container frameand permits the toner to discharge from the second toner accommodating portionto an outside (developing unit D) of the container. The toner discharged through the third openingis received through the second openingof the developing unit D.

Into the first toner accommodating portion, the toner t is supplied from the second toner accommodating portionby a second toner feeding memberrotated by a driving force applied from the main assembly by way of the developing unit D.

The description will be made further, referring back to. The recording material P set in a feeding cassetteis singled out and is fed by a pick-up rollerand a press-contact memberpress contacted thereto. In synchronism with the toner image formed on the photosensitive drum, the recording material P is fed to the transfer rolleras a transferring means, along a feeding guide.

Then, the recording material P is passed through a transfer nipformed between the photosensitive drumand the transfer rollersupplied with a predetermined voltage. At this time, the toner image formed on the photosensitive drumis transferred onto the recording material P. The recording material P having the transferred toner image is fed into a fixing meansalong the feeding guide.

The fixing meansincludes a driving rollerand a fixing rollercontaining a heatertherein. The recording material P receives heat and pressure during passing through a nipformed between the fixing rollerand the driving roller. By this, the toner image transferred onto the recording material P is fixed on the recording material P. Thereafter, the recording material P carrying the fixed toner image is further fed by a pair of discharging rollersonto a discharging tray.

The cleaning bladeis elastically contacted to the outer peripheral surface of the photosensitive drum. By this, the toner t (untransferred toner) remaining on the photosensitive drumwithout being transferred onto the recording material P is scraped off by the cleaning blade. The scraped toner t is accommodated into a removal toner accommodating portion (residual toner accommodating portion)of a frameon which the cleaning bladeis fixed.

As described hereinbefore, the image forming apparatus of this embodiment uses an electrophotographic image formation type process and forms an image on the recording material with the developer (toner). However, the image forming apparatus will suffice if an image is formed on the recording material, and the type of the image forming apparatus is not limited to the electrophotographic copying machine, the electrophotographic printer (laser beam printer, LED printer or the like), the electrophotographic printer type facsimile machine, the electrophotographic word processor or the like.

As described hereinbefore, the toner image forming portion B comprises the electrophotographic photosensitive member (photosensitive member) as the image bearing member and process means actable on the photosensitive member. In this embodiment, the toner image forming portion is detachably mountable to the main assembly of the image forming apparatus as a single cartridge or multiple cartridges.

The process means includes the charging means (charging member, charging device), the developing means (developing device, developing unit), the cleaning means (cleaning device, cleaning member).

The developing device is a device for developing an electrostatic latent image on the photosensitive member. In this embodiment, the developing device (developing unit) is formed into a cartridge which is independently detachably mountable to the image forming apparatus. On the hand, a part of the process cartridge may constitute the developing device.